Browsing by Department "Centre for Infectious Disease Epidemiology and Research"

Now showing 1 - 11 of 11
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    Open Access
    Challenges to delivering quality care in a prevention of mother-to-child transmission of HIV programme in Soweto, South Africa
    (2013) Mnyani, Coceka Nandipha; McIntyre, James
    Objectives: There has been little focus on quality of care provided in prevention of mother-to-child transmission of HIV (PMTCT) services in South Africa. We assessed quality of care in PMTCT services in Soweto, South Africa, focusing on knowledge and experiences of healthcare workers and HIV-infected pregnant women accessing the services. Methods: A cross-sectional survey was conducted between November and December 2009. A total of 201 HIV-infected pregnant women and 80 healthcare workers, from 10 antenatal clinics, were interviewed using standardised questionnaires. Results: The median gestational age at first antenatal visit was 20 weeks and 32 weeks at the time of the interview. The majority of the women, 71.5%, discovered that they were HIV-infected in the index pregnancy, and 87.9% disclosed their HIV status. Overall, 97.5% received counselling and 33.5% were members of a support group. Knowledge of antenatal and intrapartum PMTCT interventions was correct in 62.7% and 43.3% of the women, respectively. Support group membership and current use of antiretroviral prophylaxis did not impact on the quality of knowledge. Of the healthcare workers, 43.8% were professional nurses and 37.5% were lay counsellors. The majority, 80.0%, felt satisfied with their knowledge of PMTCT guidelines and 96.3% felt competent in managing HIV-infected pregnant women. Yet, there were important deficiencies in knowledge of the guidelines. Conclusion: In our study, knowledge of PMTCT interventions was low in both clients and healthcare workers. These findings point to a need to improve quality of care in PMTCT services, especially with increasingly complex PMTCT interventions recommended by international policies.
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    Comparison of six methods to estimate adherence in an ART-naïve cohort in a resource-poor setting: which best predicts virological and resistance outcomes?
    (2017) Orrell, Catherine; Cohen, Karen; Leisegang, Rory; Bangsberg, David R; Wood, Robin; Maartens, Gary
    BACKGROUND: Incomplete adherence to antiretroviral therapy (ART) results in virologic failure and resistance. It remains unclear which adherence measure best predicts these outcomes. We compared six patient-reported and objective adherence measures in one ART-naïve cohort in South Africa. METHODS: We recruited 230 participants from a community ART clinic and prospectively collected demographic data, CD4 count and HIV-RNA at weeks 0, 16 and 48. We quantified adherence using 3-day self-report (SR), clinic-based pill count (CPC), average adherence by pharmacy refill (PR-average), calculation of medication-free days (PR-gaps), efavirenz therapeutic drug monitoring (TDM) and an electronic adherence monitoring device (EAMD). Associations between adherence measures and virologic and genotypic outcomes were modelled using logistic regression, with the area under the curve (AUC) from the receiver operator characteristic (ROC) analyses derived to assess performance of adherence measures in predicting outcomes. RESULTS: At week 48 median (IQR) adherence was: SR 100% (100-100), CPC 100% (95-107), PR-average 103% (95-105), PR-gaps 100% (95-100) and EAMD 86% (59-94), and efavirenz concentrations were therapeutic (>1 mg/L) in 92%. EAMD, PR-average, PR-gaps and CPC best predicted virological outcome at week 48 with AUC ROC of 0.73 (95% CI 0.61-0.83), 0.73 (95% CI 0.61-0.85), 0.72 (95% CI 0.59-0.84) and 0.64 (95% CI 0.52-0.76) respectively. EAMD, PR-gaps and PR-average were highly predictive of detection of resistance mutations at week 48, with AUC ROC of 0.92 (95% CI 0.87-0.97), 0.86 (0.67-1.0) and 0.83 (95% CI 0.65-1.0) respectively. SR and TDM were poorly predictive of outcomes at week 48. CONCLUSION: EAMD and both PR measures predicted resistance and virological failure similarly. Pharmacy refill data is a pragmatic adherence measure in resource-limited settings where electronic monitoring is unavailable. Trial registration The trial was retrospectively registered in the Pan African Clinical Trials Registry, number PACTR201311000641402, on the 13 Sep 2013 ( www.pactr.org ). The first participant was enrolled on the 12th July 2012. The last patient last visit (week 48) was 15 April 2014.
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    Open Access
    Designing an optimal HIV programme for South Africa: Does the optimal package change when diminishing returns are considered?
    (2017) Chiu, Calvin; Johnson, Leigh F; Jamieson, Lise; Larson, Bruce A; Meyer-Rath, Gesine
    Abstract Background South Africa has a large domestically funded HIV programme with highly saturated coverage levels for most prevention and treatment interventions. To further optimise its allocative efficiency, we designed a novel optimisation method and examined whether the optimal package of interventions changes when interaction and non-linear scale-up effects are incorporated into cost-effectiveness analysis. Methods The conventional league table method in cost-effectiveness analysis relies on the assumption of independence between interventions. We added methodology that allowed the simultaneous consideration of a large number of HIV interventions and their potentially diminishing marginal returns to scale. We analysed the incremental cost effectiveness ratio (ICER) of 16 HIV interventions based on a well-calibrated epidemiological model that accounted for interaction and non-linear scale-up effects, a custom cost model, and an optimisation routine that iteratively added the most cost-effective intervention onto a rolling baseline before evaluating all remaining options. We compared our results with those based on a league table. Results The rank order of interventions did not differ substantially between the two methods- in each, increasing condom availability and male medical circumcision were found to be most cost-effective, followed by anti-retroviral therapy at current guidelines. However, interventions were less cost-effective throughout when evaluated under the optimisation method, indicating substantial diminishing marginal returns, with ICERs being on average 437% higher under our optimisation routine. Conclusions Conventional league tables may exaggerate the cost-effectiveness of interventions when programmes are implemented at scale. Accounting for interaction and non-linear scale-up effects provides more realistic estimates in highly saturated real-world settings.
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    Eliminating Vertical Transmission of HIV in South Africa: Establishing a Baseline for the Global Alliance to End AIDS in Children
    (Multidisciplinary Digital Publishing Institute, 2023-08-01) Haeri Mazanderani, Ahmad F.; Murray, Tanya Y.; Johnson, Leigh F.; Ntloana, Mathilda; Silere-Maqetseba, Tabisa; Guo, Sufang; Sherman, Gayle G.
    To gain a detailed overview of vertical transmission in South Africa, we describe insights from the triangulation of data sources used to monitor the national HIV program. HIV PCR results from the National Health Laboratory Service (NHLS) were analysed from the National Institute of Communicable Diseases (NICD) data warehouse to describe HIV testing coverage and positivity among children <2 years old from 2017–2021. NICD data were compared and triangulated with the District Health Information System (DHIS) and the Thembisa 4.6 model. For 2021, Thembisa estimates a third of children living with HIV go undiagnosed, with NICD and DHIS data indicating low HIV testing coverage at 6 months (49%) and 18 months (33%) of age, respectively. As immunisation coverage is reported at 84% and 66% at these time points, better integration of HIV testing services within the Expanded Programme for Immunization is likely to yield improved case findings. Thembisa projects a gradual decrease in vertical transmission to 450 cases per 100,000 live births by 2030. Unless major advances and strengthening of maternal and child health services, including HIV prevention, diagnosis, and care, can be achieved, the goal to end AIDS in children by 2030 in South Africa is unlikely to be realised.
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    Estimating the impact of antiretroviral treatment on adult mortality trends in South Africa: A mathematical modelling study
    (2017) Johnson, Leigh F; May, Margaret T; Cornell, Morna; Boulle, Andrew; Egger, Matthias; Davies, Mary-Ann
    Substantial reductions in adult mortality have been observed in South Africa since the mid-2000s, but there has been no formal evaluation of how much of this decline is attributable to the scale-up of antiretroviral treatment (ART), as previous models have not been calibrated to vital registration data. We developed a deterministic mathematical model to simulate the mortality trends that would have been expected in the absence of ART, and with earlier introduction of ART.
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    Hepatitis C in HIV-infected individuals: a systematic review and meta-analysis of estimated prevalence in Africa
    (2016) Azevedo, Tiago Castro Lopes; Zwahlen, Marcel; Rauch, Andri; Egger, Matthias; Wandeler, Gilles
    Although hepatitis C virus (HCV) screening is recommended for all HIV-infected patients initiating antiretroviral therapy, data on epidemiologic characteristics of HCV infection in resource-limited settings are scarce.
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    High rate of virological re-suppression among patients failing second-line antiretroviral therapy following enhanced adherence support: A model of care in Khayelitsha, South Africa
    (2013) Garone, D B; Conradie, K; Patten, G; Cornell, M; Goemaere, W; Kunene, J; Kerschberger, B; Ford, N; Boulle, A; Van Cutsem, G
    Objective. To describe and evaluate the outcomes of a support programme for patients with virological failure while receiving second-line antiretroviral therapy (ART) in South Africa.Method. We described a comprehensive medical and counselling patient support programme for patients receiving secondline ART and with two consecutive viral loads (VLs) >1 000 copies/ml. Patients with >3 months follow-up and at least one VL measurement after inclusion in the programme were eligible for analysis.Results. Of 69 patients enrolled in the programme, 40 had at least one follow-up VL and no known drug resistance at enrolment; 27 (68%) of these re-suppressed while remaining on second-line ART following enhanced adherence support. The majority (18/27; 67%) achieved re-suppression within the first 3 months in the programme. Five patients with diagnosed second-line drug resistance achieved viral re-suppression (<400 copies/ml) after being switched to third-line ART. Seven patients (7/40; 18%) did not achieve viral re-suppression after 9 months in the programme: 6 with known adherence problems (4 without drug resistance on genotype) and 1 with a VL <1 000 copies/ml. Overall, 3 patients (4%) died, 3 (4%) were lost to follow-up and 2 (3%) were transferred out.Conclusion. Our experience from a routine programme demonstrates that with targeted adherence support, the majority of patients who were viraemic while receiving second-line ART returned to an undetectable VL within 3 months. By increasing the time receiving second-line ART and decreasing the need for genotypes and/or third-line ART, this intervention may reduce costs.
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    Infant feeding knowledge, perceptions and practices among women with and without HIV in Johannesburg, South Africa: a survey in healthcare facilities
    (2016) Mnyani, Coceka N; Tait, Carol L; Armstrong, Jean; Blaauw, Duane; Chersich, Matthew F; Buchmann, Eckhart J; Peters, Remco P H; McIntyre, James A
    BACKGROUND: South Africa has a history of low breastfeeding rates among women with and without Human Immunodeficiency Virus (HIV). In this study, we assessed infant feeding knowledge, perceptions and practices among pregnant and postpartum women with and without HIV, in the context of changes in infant feeding and Prevention of Mother-to-Child Transmission of HIV (PMTCT) guidelines. METHODS: This was a cross-sectional survey conducted from April 2014 to March 2015 in 10 healthcare facilities in Johannesburg, South Africa. A total of 190 pregnant and 180 postpartum women (74 and 67, respectively, were HIV positive) were interviewed using a semi-structured questionnaire. Multiple regression analyses assessed factors associated with an intention to exclusively breastfeed, and exclusive breastfeeding of infants less than six months of age. RESULTS: Women with HIV had better overall knowledge on safe infant feeding practices, both in general and in the context of HIV infection. There were however gaps in knowledge among women with and without HIV. Information from healthcare facilities was the main source of information for all groups of women in the study. A greater percentage of women without HIV 80.9% (93/115), reported an intention to exclusively breastfeed, compared to 64.9% (48/74) of women with HIV, p = 0.014. Not having HIV was positively associated with a reported intention to breastfeed, Adjusted Odds Ratio (AOR) 3.60, 95% CI 1.50, 8.62. Other factors associated with a reported intention to exclusively breastfeed were prior breastfeeding experience and higher knowledge scores on safe infant feeding practices in the context of HIV infection. Among postpartum women, higher scores on general knowledge of safe infant feeding practices were positively associated with reported exclusive breastfeeding, AOR 2.18, 95% CI 1.52, 3.12. Most women perceived that it was difficult to exclusively breastfeed and that cultural factors were a barrier to exclusive breastfeeding. CONCLUSIONS: While a greater proportion of women are electing to breastfeed, HIV infection and cultural factors remain an important influence on safe infant feeding practices. Healthcare workers are the main source of information, and highlight the need for accurate and consistent messaging for both women with and without HIV.
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    Nitroblue tetrazolium: its use in the diagnosis of infection and in the study of leukocytes, lipoproteins and liposomes
    (1974) Segal, Anthony Walter
    A rapid, objective indicator of pyogemc infection would be of great value in the practice of clinical medicine. On the basis of earlier studies it was claimed that the nitroblue tetrazolium ( NBT) test might fulfill such a role. In view of the potential value of this test, it was reassessed m order to determine its diagnostic accuracy and clinical value. The results obtained in this study did not conform with those previously published. Elevated NBT scores were not diagnostic of pyogenic infection, there was a wide overlap of the results of tests performed on patients with pyogenic disease, patients with other diseases and normal subjects. In addition, there was a significant observer error in the interpretation of the slide preparations. The extent of this error was reduced with experience, but was still considerable in the hands of experienced observers. In the NBT test, the dye enters neutrophils by phagocytosis of NBT in particulate form, complexed to heparin and/or '·fibrinogen. The proportion of neutrophils which phagocytose these complexes seems to be related to the severity of illness of the patient. As serum from these patients is capable of enhancing phagocytosis of complexed dye by normal cells, a humeral factor could be responsible for the increased phagocytosis of complexed NBT indicated by a positive test. , Of the compounds tested, man m vitro model system designed to simulate the NBT test, 3 a,l_acid glycoprotein, immunoglobulins and endotoxin, in concentrations that occur in vivo, enhanced NBT reduction. Any one of these compounds, singly or in combination, could be responsible for positive NBT tests.
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    Prevalence of hepatitis B and C infection in persons living with HIV enrolled in care in Rwanda
    (2017) Umutesi, Justine; Simmons, Bryony; Makuza, Jean D; Dushimiyimana, Donatha; Mbituyumuremyi, Aimable; Uwimana, Jean Marie; Ford, Nathan; Mills, Edward J; Nsanzimana, Sabin
    BACKGROUND: Hepatitis B (HBV) and C (HCV) are important causes of morbidity and mortality in people living with human immunodeficiency virus (HIV). The burden of these co-infections in sub-Saharan Africa is still unclear. We estimated the prevalence of the hepatitis B surface antigen (HBsAg) and hepatitis C antibody (HCVAb) among HIV-infected individuals in Rwanda and identified factors associated with infection. METHODS: Between January 2016 and June 2016, we performed systematic screening for HBsAg and HCVAb among HIV-positive individuals enrolled at public and private HIV facilities across Rwanda. Results were analyzed to determine marker prevalence and variability by demographic factors. RESULTS: Overall, among 117,258 individuals tested, the prevalence of HBsAg and HCVAb was 4.3% (95% confidence interval [CI] (4.2-4.4) and 4.6% (95% CI 4.5-4.7) respectively; 182 (0.2%) HIV+ individuals were co-infected with HBsAg and HCVAb. Prevalence was higher in males (HBsAg, 5.4% [5.1-5.6] vs. 3.7% [3.5-3.8]; HCVAb, 5.0% [4.8-5.2] vs. 4.4% [4.3-4.6]) and increased with age; HCVAb prevalence was significantly higher in people aged ≥65 years (17.8% [16.4-19.2]). Prevalence varied geographically. CONCLUSION: HBV and HCV co-infections are common among HIV-infected individuals in Rwanda. It is important that viral hepatitis prevention and treatment activities are scaled-up to control further transmission and reduce the burden in this population. Particular efforts should be made to conduct targeted screening of males and the older population. Further assessment is required to determine rates of HBV and HCV chronicity among HIV-infected individuals and identify effective strategies to link individuals to care and treatment.
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    The case for Option B and Optional B+: Ensuring that South Africa’s commitment to eliminating mother-to-child transmission of HIV becomes a reality
    (2012) Besada, D; Van Cutsem, G; Goemaere, E; Ford, N; Bygrave, H; Lynch, S
    In a previous issue of the Southern African Journal of HIV Medicine, Pillay and Black summarised the trade-offs of the safety of efavirenz use in pregnancy (Pillay P, Black V. Safety, strength and simplicity of efavirenz in pregnancy. Southern African Journal of HIV Medicine 2012;13(1):28-33.). Highlighting the benefits of the World Health Organization’s proposed options for the prevention of mother-to-child transmission (PMTCT) of HIV, the authors argued that the South African government should adopt Option B as national PMTCT policy and pilot projects implementing Option B+ as a means of assessing the individual- and population-level effect of the intervention. We echo this call and further propose that the option to remain on lifelong antiretroviral therapy, effectively adopting PMTCT Option B+, be offered to pregnant women following the cessation of breastfeeding, for their own health, following the provision of counselling on associated benefits and risks. Here we highlight the benefits of Options B and B+.